Conventionally, when a copier reads an original document on which golden or silver characters or images having a mirror reflection property are printed, there is a problem that the characters or images having a mirror reflection property are black in the read image. A copier has a structure for reading the light reflected from an original document with an image sensor. Thus, the characters having a mirror reflection property reflects the light emitted from a light source; however, as there is no reflected light towards the image sensor, the characters having a mirror reflection property are black.
As an existing technology for addressing such a problem, the technology is known which has been disclosed in Japanese Unexamined Patent Application Publication No. 2013-5334 and which relates to an image reading apparatus.
However, the foregoing conventional technology refers to a structure in which a plurality of light sources and light-transmitting members are assembled and therefore has disadvantages including complicated structure and expensive cost.